The absolute quickest way to obtain a UK passport in 2026 is through the Online Premium Service. This service allows you to book an appointment at a regional passport office, where your new passport will be ready to collect as soon as four hours after your appointment concludes. However, this is strictly for adult passport renewals and requires you to attend an in-person appointment. If you need a more flexible option, the 1-Week Fast Track Service is available for child passports, first-time adult passports (in limited cases), and renewals, delivering the document to your home via courier within seven days of your appointment. For both services, you must book an appointment online via GOV.UK, and slots are often in high demand, so it is a peer-to-peer recommendation to check for new appointments early in the morning. Note that if you are applying for your very first adult passport, you are generally not eligible for the 1-day service and must use the standard or 1-week routes.